.nav-bar {
    position: relative;
    height:56px;
    z-index: 10;
    width: 100%;
    overflow: hidden;
}
.main-nav-bar {
    position: fixed;
    z-index: 10;
    bottom: 0;
    width: 100%;
    overflow: hidden;
    background-color: #fff;
    box-shadow: 0 0 10px #999;
}
.main-nav-bar li {
    float: left;
    height:56px;
    overflow: hidden;
}
.main-nav-bar li a {
    position: relative;
    display: block;
    height: 100%;
    text-align: center;
    font-size: 14px;
    color: #999;
    background-size: 22px;
    background-position: center 8px;
    background-repeat: no-repeat;

}
.main-nav-bar li a span {
    position: absolute;
    left: 0;
    bottom: 0;
    display: block;
    width: 100%;
    height: 24px;
    line-height: 24px;
}
.main-nav-bar li.active a span {
    color: #ef3946;
}
.nav-btn-1 { background-image: url('../img/main-nav-1.png')}
.nav-btn-2 { background-image: url('../img/main-nav-2.png')}
.nav-btn-3 { background-image: url('../img/main-nav-3.png')}
.nav-btn-4 { background-image: url('../img/main-nav-4.png')}
.active .nav-btn-1 { background-image: url('../img/main-nav-active-1.png')}
.active .nav-btn-2 { background-image: url('../img/main-nav-active-2.png')}
.active .nav-btn-3 { background-image: url('../img/main-nav-active-3.png')}
.active .nav-btn-4 { background-image: url('../img/main-nav-active-4.png')}

.main-nav-bar.hide{
    display: none
}